Typical disc cutterbars used in agriculture include a side-by-side row of cutterheads. Some cutterbars utilize components including a train of meshed spur gears for driving the individual cutterheads, and others utilize a train including a main power shaft coupled by respective bevel gear sets, for delivering power to the respective cutterheads. The cutterheads each typically comprise a cutting disc including diametrically opposed cutting blades (though configurations with three or more blades are known) and having a hub coupled to an upper end of a drive shaft, the lower end of the drive shaft carrying a spur gear in the case where a train of meshed spur gears is used for delivering power, and carrying a bevel gear of a given one of the bevel gear sets in the case where a main power shaft is used. In both cases, the components of the cutterheads include bearings which support the shafts and gears. The cutting blades and discs are rotated at a relatively fast speed, and are susceptible to contact with hard objects, making the drive components, such as gears, bearings, and shafts vulnerable to damage and wear, and ultimately, failure. For background information on the structure and operation of some typical disc cutterbars, reference is made to E. E. Koch and F. F. Voler, U.S. Pat. No. 4,815,262; and Campbell et al., U.S. Pat. No. 5,996,323, the descriptive portions thereof being incorporated herein in full by reference.
When a component of a cutterhead, particularly, a gear or bearing, fails, hard metallic particles of the component may enter other components, such as bearings, or the interfaces between other components, such as enmeshed gear teeth, so as to cause possibly catastrophic secondary damage. Additionally, when a component breaks, proper repair may entail removing and cleaning the resulting particles from other components which may have received or picked up the particles from the failed component, which can be a time-consuming and expensive process. In this regard, some cutterbars utilize a common oil sump for all or some number of the cutterheads, such that failed component particles and broken pieces can be distributed throughout all or a large portion of the cutterbar, or at least to other components of the cutterbar, necessitating disassembly and cleaning all potentially exposed areas of the cutterbar, which greatly increases the time and expense of the repair.
It has been found that at some time prior to the onset of actual serious component failure wherein secondary damage is more likely to occur, which prior time is herein defined as an impending failure, the components may generate certain indicators of, or clues to, the impending failure, which indicators can include, but are not limited to, conditions such as increased heat, increased or changing sounds, and/or vibrations, which indicators may be different from the indicators of an actual, serious failure involving secondary damage or possibility thereof. It has been further surmised that if such indicators could be detected prior to onset of actual component failure and the effects that can lead to possible resultant damage to other components, repairs could be made more easily, inexpensively, and timely.
However, indicators of impending failure will typically be more subtle compared to those of actual failure, or significant onset thereof. Therefore, to detect impending failure, as opposed to actual onset of significant failure or damage, leading to problems such as metallic particles circulating through the oil sump and entering other components, it will be necessary to identify the indicators of the impending failure, and have the capability to detect or sense them when present. It will further be necessary to have the capability to distinguish the indicators from other, normal operating parameters or characteristics which will be present during operation of the cutterbar, and also detectable by whatever sensing or detecting medium is used. Still further, it is contemplated that, over time, or with changing conditions, such as, but not limited to, environmental changes, load changes, operation on different grades and slopes, normal wear, and the like, the characteristics and/or parameters used as the indicators may change, some more than others, but not in a manner so as to indicate an impending failure. As a result, it will be desirable to have a capability to recognize and adapt to such changes and variations, so as to have a capability to recognize when one or more of the characteristics and/or parameters used as the indicators, are sufficiently different from the others so as to indicate an impending failure.
Accordingly, what is sought is a system and method for detecting an impending failure, or initial onset of failure, of a component or components of an individual cutterhead of a cutterbar, before serious damage is likely to occur, to enable taking corrective action for avoiding actual failure of the component and possible secondary problems set forth above.